Number sequence puzzles are very popular of late.</sarcasm>
Therefore, I present to you another one. I promise you it has no relation to any sequence in OEIS, nor will it ever be found there, and it does not require any mathematics at all to be solved. It is also not based on a language.
What are the next numbers in the following sequence?
1, 2, 7, 12, 13, 16, 18, 19, 20, ...
The sequence will always be finite, but it grows every day.
Every one of you has seen some elements of this sequence.
There is a related sequence which contains most (but not all) numbers not appearing in this sequence. It starts with 4, 5, 6, 8, 14, 15, 21, 23, 24, ...
I have made some contributions to this list, but only a handful. The person contributing the most has over 200 entries.